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by Virginia Bourdeau
I'm an ecologist and outdoor educator by training and
profession. On my first day of work at the Oregon 4-H Center in 1985,
the most sophisticated technology in the office was an electric typewriter.
If you wanted a copy of your document, you used carbon paper. Over the
years, I've learned to use evolving versions of computers and software
systems, photo copiers, and fax machines. Thanks to my daughter's
tutelage, I can retrieve the voice mail from my cell phone. But, I am
not anyone's idea of an "earlier adopter." My husband
has been known to tell me to drag myself into the 21st Century.
So when my supervisor appeared at camp in the fall of 2004 with a "gift" of
28 shiny new GPS units, I greeted him with limited enthusiasm. He, of
course, was very excited about this innovative new program delivery for
4-H that he was funding. His idea was for me to design lessons and train
4-H staff and volunteers to support technology education at the 4-H Center
and in the local counties. All I could think was it was a good thing
I had a few months until our spring field season started.
Creating an
Educational Experience at Camp
Our GPS lessons begin with a very basic
map and compass lesson. It is important for campers to understand the
basis for the data and functions of the GPS units. A globe and four small
flashlights are used to illustrate the satellite system. Four campers
assist with this demonstration intersecting the beams of four flashlights
over the 4-H Center's intersecting longitude and latitude on the
globe. Next, campers find the same longitude and latitude on a local
topographic map. When the compass directions and map reading are understood,
we move outside to introduce the GPS units.
Each camper is given a unit
with instructions to put the cord around his/her neck. The units are
turned on, and campers watch as satellite signals are acquired. This
can take some time, especially if there is cloud cover. An activity location
with a clear view of the sky, such as a large meadow, is essential. When
all the GPS units indicate they are "ready to navigate," the
next step is to calibrate the compass. Campers learn to move through
the display screens, called pages, to locate the navigation page. A handout
assists campers to follow the steps to calibrate the compass.
Still working as a group, campers are asked to proceed to the GPS units
page where they can enter a waypoint in the location screen. The units
have a drop-down menu with a small numerical key pad that allows campers
to enter the longitude and latitude of a given waypoint. They will need
to master use of the "click stick" on the GPS unit to enter
waypoints. This tends to be easier for youth than adult learners to master.
For the introductory activity, all campers enter the same waypoint.
When the waypoint is entered in the unit, the GOTO feature is selected.
This automatically transfers the unit to the navigation page with a compass
and a direction of travel arrow pointing to the waypoint. Before the
group moves off, they select a buddy to walk with and are reminded to stay
on the trails to avoid contact with poison oak. The pairs of campers
eventually all arrive at the amphitheater.
In the first year of the program,
we set up a waypoint trail of geocaches. Bright orange beach sand pails
were used for the geocaches to assist campers to locate them even on
days when the unit's accuracy was low. Each team of campers was
given a team name and a starting waypoint clue that took them to their
first geocache. When they arrived at that geocache, they took their team's
next clue out of the bucket and entered the waypoints into their units.
This proceeded until all teams arrived back at the amphitheater— the
final waypoint for all teams.
In our second summer, we decided to combine
teaching GPS technology with an activity to teach campers about some
local tree species. We created a Tree Identification Waypoint Trail.
A set of handouts gives the coordinates of some selected trees, along
with tree identification information and pictures. Trees were selected
to be relatively easy to locate even on days when the GPS unit's accuracy
was low. At each tree, campers are asked to perform a task such as take
a bark rubbing, draw a seed or cone, or draw the outline of a leaf. Campers
always do the activity in twos or threes so they are not alone at any
time as they move around camp. Each set of handouts has the trees presented
in a different order. This helps minimize teams of campers arriving at
the same tree at the same time or following another camper team, rather
than entering the waypoint coordinates in their own units. The repetition
of entering the coordinates into the GPS units to locate each tree builds
the camper's confidence to use the units for real tasks.
Advancing to GPS Mapping
Older learners enjoy learning to use the GPS
units to make simple maps. In this activity, campers practice saving
waypoints for the specific locations they want to map. The Zoom In feature
of the map page is used to scale the map to show a route campers can
walk in the activity. Before beginning this lesson, the activity leader
should make sure that the GPS units do not have any stored waypoints,
tracks, or routes from previous activities.
Waypoints are saved in the
GPS unit on the same page that the waypoints are entered in the introductory
activity. When the location page is opened, the coordinates for that
specific location can be saved. Campers can name the location they are
saving by highlighting the number given to the waypoint by the GPS unit.
If all the previous waypoints have been deleted, this number will show
as 001. A drop-down menu is provided that includes an alphabet and number
pad. We generally start this lesson at our swimming pool. Campers are
asked to enter the letters p-o-o-l using the keypad and the click stick.
They can also change the GPS unit's standard map symbol by opening
a drop-down menu where they can select a specific symbol for their waypoint.
If all these entries are saved correctly in the GPS unit, campers will
find the word "pool" and the map symbol they selected displayed
on the unit's map page.
Campers work in teams to save several more
waypoints and then return to an agreed-upon location. If time remains
in the lesson, they can exchange GPS units and use the GOTO feature to
retrace another team's map.
For camps wishing to make use of GIS
(geographic information systems), saved waypoints can be used to make
site maps using specific computer software. Campers generally are satisfied
with the maps they create on their units. We have used a software interface
and computer to make "you are here" site maps for our buildings
and some outdoor locations. We will begin to use GIS to assist in planning
the on-site forestry management in 2007.
Teaching the Old Educator New Tricks
I have learned to be a fan of GPS
technology. The lesson which combines the GPS units with a tree activity
has campers, who would never sign up for a tree ID class, learning a
few trees—almost by accident.
We have used these lessons with campers
from fourth grade up. We even did a lesson for our Board of Directors
when they had their summer meeting at camp! The speed of the units in
locating satellites and the changeable accuracy make them difficult to
use with campers below the fourth-grade level. For safety, the GPS activity
should be set up in an area which can be easily supervised, and campers
should travel in teams.
GPS units generally come preprogrammed with maps.
In addition, they may include sun and moon phase data, calendars, calculators,
and other features. These features may support other types of on-site
camp programming and trip/travel and survival training camps as well.
Camper evaluations indicate this class is meeting its goals. One camper
wrote, "I learned a lot in your class. I think everyone should
know the things you teach in your class because anyone can get lost but
only some can become unlost." I'm glad I learned to use this
new technology and can give campers the skills to become "unlost."
Reference
Hurn, J. (1989). GPS: A Guide to the Next Utility. Sunnyvale,
CA: Trimble Navigation.
What Is GPS Anyway?
"GPS" is short for Global Positioning System. The system
is not just the hand-held field unit or the computer in your car.
GPS includes a constellation of twenty-four satellites orbiting
the Earth at a very high altitude. The U.S. government, primarily
the Department of Defense, has invested over $12 billion to build
this satellite system (Hurn 1989).
The satellites send radio waves
that allow the receiver in the GPS unit to determine the distance
from the unit to the satellites using the formula: Distance = speed
of light (186,000 miles per second) X time. GPS receivers are able
to determine time through decipherment of a code that is sent by
both the satellite and the receiver at the same time. The difference
between the time that the receiver sends the code and receives
the code is the time that it takes to get from the satellite to
the receiver.
Timing accuracy between the satellites and the earthbound
receivers is extremely important. Each satellite is equipped with
four atomic clocks, the most stable and accurate time reference
available, which cost about $100,000 each (Hurn 1989). A standard
GPS unit includes a moderately accurate clock. To eliminate any
timing offset between the extreme accuracy of the satellite’s
clocks and the GPS units, the units must locate and receive information
from multiple satellites. Most GPS units need to be receiving information
from a minimum of four satellites before they tell the user they
are "ready to navigate."
When a GPS unit is ready to
navigate, it will display its current location as latitude and
longitude; for example, Location: N 45°00.213, W 123°08.750.
Remember your geography lessons? Lines of latitude run parallel
to the equator. N 45° is the latitude reading. Lines of longitude
run north to south and intersect the poles. W 123° is the longitude
reading. The intersection of the latitude and longitude lines is
displayed on the screen as the unit’s location.
The two primary
ways to use a GPS unit is to either (1) store longitude and latitude
coordinates, called waypoints, when moving from one location to
another along a trip or trail, or (2) to enter waypoints into the
unit and use the unit’s "GOTO" feature to get
travel directions. The units can also tell you your current altitude
and include a compass and a trip computer.
Readers may be familiar
with using navigation units in cars, which use GPS technology and
electronic maps, or with a GPS recreation activity called geocaching.
Geocaching is a popular outdoor recreation activity which uses
waypoints, provided on Internet sites by participants. There is
a specific etiquette for each geocache. Visitors to a geocache
may be asked to sign a book or leave a trinket, in exchange for
taking a trinket. An Internet search will provide interested persons
a wealth of information about this activity.
When shopping for
GPS units, be sure you know the accuracy of each brand under consideration.
In the performance specifications of the owner's manual of
the units I was using, it stated GPS Accuracy: < 15 meters (49
ft.), 95% typical. A footnote said, "Subject to accuracy
degradation to 100 m 2 DRMS under the U.S. Department of Defense
imposed Selective Availability program." This means not all
satellites are available for civilian use all the time.
This level
of accuracy is fine when the user is locating a geocache. However,
on "camp scale" it is a drawback that activity leaders
must understand. The 4-H Center’s property is over 300 acres,
but the main lodging and program sites occupy less than twenty
acres. Any activity in this size area will necessarily have waypoints
in close proximity. |
Originally published in the 2007 November/December
issue of Camping Magazine. |
